This invention relates generally to membrane or sheet liners which may be used, for example, to line containment structures, such as landfills for hazardous or non-hazardous waste disposal, water or other fluid containments or to cover such containments to prevent the encroachment of storm water or the escape of odors and fumes.
Conventionally, earthen structures or natural depressions form the containment volume. Substantially impermeable membrane sheets are then utilized to reduce or minimize leakage of the contained material. These substantially impermeable sheets are frequently described as "geomembranes".
The size and/or geometry of the containment may require that a multiplicity of membrane sheets be used to cover the total area to be protected from excessive leakage. As a result a number of seams between edges of adjacent membrane sheets must be sealed to assure the desired reduction of containment leakage.
The edges of adjoining membrane sheets may be heat fused and thereby sealed and joined together in a leakproof fashion. Alternatively, adhesives or chemicals that fuse adjoining edges together may be used-to join and seal the edges of some types of membranes.
Forming an adequately effective, leak resistant containment membrane seal is labor intensive and requires significant skills, training, tools, supplies and equipment. Commonly used sealing procedures may be adversely affected by moisture and inclement weather.
Thus, there is a need for an effective, suitably leak resistant seam that reduces the disadvantages of the current practices.